For example, in a tilt and/or telescopic type steering column apparatus for a vehicle, a steering column is so constructed as to be tiltable and telescopically slidable, and a column sided bracket (distance bracket) attached to the steering column can be pressure-contacted to a car body sided bracket (tilt bracket) attached to a car body.
A fastening bolt is inserted through a tilt adjustment elongate hole formed in the car body sided bracket and through a telescopic adjustment elongate hole formed in the column sided bracket. A manipulation lever of a clamp mechanism is connected to one side end of this fastening bolt via a cam mechanism and a screw mechanism. With this construction, the fastening bolt is fastened by rotating the manipulation lever in one direction, whereby the two brackets are pressure-contacted to each other and fixedly fastened in a tilt and/or telescopic adjustment position. On the other hand, the fastening bolt is slackened by rotating the manipulation lever in a reverse direction, thereby releasing the two brackets from being pressure-contacted, the tilt and/or telescopic adjustment can be thus performed.
When making the tilt adjustment, the fastening bolt moves substantially in up-and-down directions together with the steering column and the column sided bracket along within the tilt adjustment elongate hole formed in the car body sided bracket.
BY contrast, when making the telescopic adjustment, the steering column and the column sided bracket move substantially in front-and-rear directions of the vehicle along within the telescopic adjustment elongate hole in a way that gets the fastening bolt to engage with the telescopic adjustment elongate hole.
By the way, each of the tilt adjustment elongate hole and the telescopic adjustment elongate hole has a slight gap with respect to the fastening bolt. With this contrivance, the fastening bolt can be smoothly moved along within the two adjustment elongate holes when making the tilt and/or telescopic adjustment, and the tilt and/or telescopic adjustment operation is kept preferable.
Further, when in a tilt and/or telescopic fastening operation, the car body sided bracket and the column sided bracket are pressure-contacted to each other, and hence the backlash does not occur between the two adjustment elongate holes and the fastening bolt even if each of these two adjustment holes has such a slight gap.
When making the tilt and/or telescopic adjustment, especially when in the tilt adjustment, the backlash between the two adjustment elongate holes and the fastening bolt and emission of butting noses, might be caused due to the slight gaps described above on the occasion of the relative movement of the fastening bolt to the two adjustment elongate holes.